Opuntia leptocarpa is a prickly pear cactus that grows in east-central and central TX, and areas extending from there. It grows with O.macrorhiza and O.lindheimeri. Plants are not numerous in most locations.
Stems are ascending, typically less than 30(50) cm. Pads are thin and oval, obovate, or elliptic, 10 to 20(25) cm long. Spines may be tan (or cream-yellow) darkening to brown or red-brown at the base, 20-30 mm long. Older cladodes may lack spines altogether.
Flower buds are thin and have rust-colored glochids. Anthers are yellow and filaments are yellow-white or white. The stigmas are pale white, yellow, or green. Tepals are gold-yellow or canary yellow. Inner tepals typically have at least a small amount of reddish pigment at their bases. As the name implies, the pericarp and the fruit may be long and slender.
Ploidy is unknown.
Some botanists suggest this taxon is the same as O.pyrocarpa, but we have observed it forms smaller plants with more slender flower buds. Britton and Rose described O. leptocarpa as a possible hybrid of O.macrorhiza and O.lindheimeri, which seems unlikely.